In modern building construction, electrical wires are often run in conduit, such as "EMT" (electrical metallic tubing), "IMC" (intermediate metallic conduit), "GRC" (galvanized rigid conduit) or PVC (polyvinylchloride) coated EMT, IMC or GRC. The tubing is first installed in the building and then the wires are pulled through it. When installed, the electrician frequently has to bend the tubing in order to route it between locations. Bends are commonly made with tools which are adapted for making a bend in a single direction in the tubing, for example, a 22.5.degree., 30.degree., 45.degree., 60.degree. or 90.degree. bend. However, when running a straight run of tubing and an obstruction is encountered, it is sometimes necessary or desirable to simply offset the tubing to go around the obstruction, i.e., the two ends of the tubing on either side of the bend end up parallel to one another. This type of bend is referred to as an offset bend. When two offset bends are made in the same plane to bring the ends into axial alignment with one another, it is know as a four point offset bend. When using the typical type of tool that bends in a single direction, for each offset bend, it requires that two bends be made of the same angle, with care given that the tubing on both sides of the two bends ends up parallel and in the same plane. If several pieces of tubing must be bent or if four point offset bends are made, the individual offset bends should be consistent, to produce a professional looking job.
Machines have been made which are particularly adapted to making offset bends. For example, U.S. Pat. Nos. 5,222,384; 4,829,806; 3,875,786; and 3,691,815 disclose such bending machines. However, a need continues to exist for a conduit bender which is capable, in a practical manner, of providing consistent, accurate, and variable offset bends.